Reflectors in stoves/heating boxes of stretch blow moulding machines are known, wherein a reflector material made of ceramic materials is used. From WO 2006/002751 A1, a heating stove for preforms is known. This heating stove includes means for receiving and transporting the preforms through the apparatus. Further, a counter reflector for the radiation source is provided which is profiled on the surface that faces the preform. Whilst on the one hand, an improved heat input into the preforms is achieved by means of this profiling, on the other hand, however, this surface is relatively hard to clean and therefore performance losses may result in the course of time due to contamination and oxidisation.
In DE 197 24 621 B4, a method and an apparatus for heating preforms are described. The preforms are moved herein past radiant heaters and the radiant heaters are acted upon by focusing elements, wherein the heating radiation is reflected by a primary mirror onto a secondary mirror. Whilst this procedure also allows an improved input of heat into the preforms, however, the apparatus is relatively hard to clean.
One problem with the apparatuses known from the prior art is the high energy demand resulting from the heating of plastic preforms.
It may therefore be desirable to provide methods and apparatuses for heating preforms with substantially improved efficiency and thus energy savings.